RESUMO
Atrial fibrillation (AF) is the most common cardiac arrhythmia that can potentially result in stroke. Vitamin K antagonists (VKA) like warfarin were for many decades the only oral anticoagulants available for stroke prevention in patients with non-valvular atrial fibrillation (AF) at high risk of stroke. Recently, new oral anticoagulants (NOACS) have been introduced that act via direct inhibition of thrombin (dabigatran) or activated factor X (edoxaban, rivaroxaban and apixaban). Unlike VKAs, these anticoagulants do not require routine INR monitoring and posses favorable pharmacological properties. NOACs act rapidly, and have a stable and predictable dose-related anticoagulant effect with few clinically relevant drug-drug interactions. Phase III trials comparing these agents to warfarin for stroke prevention in patients with non-valvular AF demonstrated that they are at least as efficacious and safe as warfarin. Evolution of clinical guidelines to incorporate the new anticoagulants for stroke prevention in non-valvular AF may result in a reduction in the incidence of AF-related strokes. Safe and effective use of these new drugs in clinical practice requires understanding of their distinct pharmacological properties.
